Organic modification of layered silicates as barrier pigments in coating systems

 
Corrosion of components causes total annual damage of around 4% of GDP. Corrosion as a cause of damage is thus on a par with material failure due to wear and tear. To protect components, functional coatings and the barrier pigments they contain are an indispensable part of corrosion protection. In their pure form, the layered silicates frequently used for this purpose often do not achieve a sufficient effect for the complete protection of components. The barrier effect of silicates can be significantly improved by targeted organic modification. If the effect of commercial silicates is compared to modified variants, the unmodified silicates show an improvement in the barrier of around 20%. In contrast, the pigments produced by preparation achieve an improvement of up to 80%. The phyllosilicates used in these coatings were used as barrier pigments to extend the diffusion path and thus improve the barrier properties. The exfoliationof the silicates has a decisive influence on the subsequent functionality of the barrier. Due to the large number of coating systems and the associated binder classes, the silicates have to be specifically matched to the respective polymer.